The visitors held on till the 52nd minute before going two down, courtesy of back-to-back strikes from Nuno Gomes and Cristiano Ronaldo.

Porto winger Ricardo Quaresma added a superb third with a trade-mark shot to mark his first international goal, Ronaldo completed his brace in the 75th minute to complete the rout.

In the same group, minnows Kazakhstan produced a huge shocker when they beat Serbia 2-1 to record their first ever competitive victory.

Portugal are third in the group, three points adrift of leaders Poland who thrashed Azerbaijan 5-0 to go top with the Portugeuse having a game in hand.

In Group D, a double salvo from Schalke striker Kevin Kuranyi helped Germany to a vital 2-1 away win at Czech Republic to take charge of the group, leading the Czechs by 3 points.

Kuranyi fired in two headers in the 42nd and 62nd minutes to beat Petr Cech.

The hosts found the net later when Jan Polak's shot was awkwardly deflected home by Milan Baros for a 77th minute consolation goal.

Republic of Ireland capitalized on Germany's win to level on points with second placed Czech Republic after beating Wales 1-0, thanks to a 39th minute strike from Manchester City youngster Stephen Ireland.

Spain kept their qualifying hopes alive with a 2-1 victory over Denmark at the Santiago Bernabeu in Group F.

Valencia duo Fernando Morientes and David Villa scored in the 34th and 44th minutes respectively before Michael Gravgaard pulled one back for Denmark early in the second half.

David Healy notched his second hat-trick of the qualifiers to help Northern Ireland to a 4-1 win over underdogs Liechtenstein at Windsor Park and move to second place in Group F.

Sweden are in charge of the group on 12 points, while Spain are in critical situation lying fourth with 6 points from 4 games, trailing Denmark by one point.

In Group G, Holland remain top with 11 points despite being held to a goalless draw at home by Romania.

The Romanians are level with Bulgaria on 8 points in second place.